EP 0231404 B1 19901212 - EARTH PRESSURE SHIELD
Title (en)
EARTH PRESSURE SHIELD
Publication
Application
Priority
EP 86100197 A 19860109
Abstract (en)
[origin: EP0231404A1] In an earth pressure shield for the extraction of plastic, mechanically transportable ground with a deflecting wall closing off the extraction chamber at the rear, in which the deflecting wall can be designed as a rotating drum connected to the extracting tool or as a fixed bulkhead wall, which earth pressure shield has means of preparing the loosened ground by the addition of plasticising means, the supporting pressure on the face is kept constant by the homogenising means fed to the front chamber (6, 13). For this purpose, the annular chamber (5, 12) between the bulkhead wall (2) and the deflecting wall (4, 11) is acted upon with homogenising means at a certain pressure level - at least the requisite supporting pressure for the face. The homogenising means flows through at least one non-return valve (7), arranged on the surface of the deflecting wall (4), out of the annular chamber (5, 12) into the front chamber (6, 13). The non-return valve (7) closes when excess pressure prevails in the front chamber (6, 13) relative to the annular chamber (5, 12) and opens when the pressure in the front chamber (6, 13) is less than in the annular chamber (5, 12). <IMAGE>
IPC 1-7
IPC 8 full level
E21D 9/08 (2006.01); E21D 9/087 (2006.01)
CPC (source: EP)
E21D 9/0879 (2016.01)
Designated contracting state (EPC)
BE DE FR NL
DOCDB simple family (publication)
EP 0231404 A1 19870812; EP 0231404 B1 19901212; DE 3676184 D1 19910124
DOCDB simple family (application)
EP 86100197 A 19860109; DE 3676184 T 19860109